La Réunion and Mayotte cockroaches: impact of altitude and human activity

Competitive displacement is the outcome of interspecific competition between invading and native species. Alien insect species invade not only cultivated areas but also natural habitats. We prospected the cockroach fauna on two oceanic islands (Mayotte and La Réunion) to investigate the impact of altitude and anthropic disturbance on the distribution of these species. Most invading cockroach species seem to benefit from cultivation of land whereas endemic species occupy more specific and reduced habitats that are threatened by human impact.     

Changes in R–R variability before and after endurance training measured by power spectral analysis and by the effect of isometric muscle contraction

 The long-term conditioning effects of physical training on cardiorespiratory interaction in 11 young healthy males were studied. Significant increases in maximum oxygen uptake (V˙O_2max)(P<0.05) and decreases in heart rate (P<0.05) were achieved in all subjects following a 6-week training programme consisting of cycling for 25min each day at a work level that increased heart rate to 85% of maximum. Heart rate variability, measured as the differences between the maximum and minimum R–R interval in a respiratory cycle, increased in nine of the subjects and decreased in two. The respiratory-cycle-related high-frequency peak in the power spectral plot of R–R variability also showed significant increases in the same nine subjects and decreases in two. The latter result was similar after normalisation of the data for changes in heart rate by calculating the common coefficient of variance (CCV=HFR–R×<∮∮), where HF is the high-frequency component of the power spectral plots, using a further measure of vagal tone it was shown that, for all subjects, the R–R interval change in response to isometric contractions of the arm flexors in one respiratory cycle were significantly greater after training. These data suggest that cardiac vagal tone is increased by aerobic training for all subjects and that this is accompanied by a respiratory sinus arrhythmia (RSA) in most, but may be associated with a decrease in RSA in subjects with a very low (< 50 beats⋅min^-1 heart rate. Accepted: 23 April 1996     

Karyological and serological studies in Rana lessonae,R. ridibunda and in their hybrid R. ‘esculenta’ (Amphibia,Anura)

The karyotypes of the three water frog forms: Rana lessonae, R. ridibunda and R. esculenta were analysed from bone marrow cell preparations of animals captured in several localities of the GDR. In the three forms chromosome morphology was similar (5 large and 8 small pairs), although differences in the relative length of most elements were found; R. esculenta chromosomes were always intermediate.One of the small pairs (Chr. 12) was found to be metacentric in R. lessonae and submetacentric in R. ridibunda. Most R. esculenta individuals examined had one meta-and one submetacentric 12th element, indicating the hybrid nature of this form. However 16.6% esculenta proved to be homozygous for either the metacentric or the submetacentric chromosome 12, while 13% lessonae individuals and 7.7% ridibunda were heterozygous for this element.By starch gel electrophoresis an analysis was undertaken of serum proteins from water frogs coming from regions in which the forms occur together (sympatric populations) and from zones in which only one of them lives (allopatric populations).In Rana lessonae, where only one allele had been previously described, two different alleles were found in animals coming from the GDR.If genetic polymorphism is excluded, between 6.1% and 9.1% individuals from sympatric lessonae and ridibunda populations showed introgression of an albumin allele. No gene introgression was found in allopatric lessonae populations from the Leningrad region or in ridibunda from Alma Ata and southern Bulgaria.     

R—Factors of Escherichia coli from Dressed Beef and Humans

One hundred eighty Escherichia coli strains isolated from raw and cooked dressed beef and from healthy humans were screened for resistance to each of nine antibiotics: chlortetracycline, ampicillin, chloramphenicol, kanamycin, neomycin, nalidixic acid, dihydrostreptomycin, oxytetracycline, and tetracycline. Nearly 80% of the 98 beef isolates and 54% of the 82 human isolates were resistant to one or more of the antibiotics tested. Ampicillin resistance was most frequent among beef isolates, and dihydrostreptomycin resistance was most frequent among isolates of human origin. About 74% of the multiply resistant beef strains and 85% of the multiply resistant human strains transferred all or part of their resistance to E. coli K-12 recipients.     

Natural and Recombinant Soluble Low-Affinity FcγR: Detection,Purification, and Functional Activities

Studies on the identification, cloning, and biochemical characterization of natural and recombinant human and mouse low-affinity soluble FcγR (sFcγR) have been developed using various methods. RT-PCR and/or biochemical analyses have demonstrated that low-affinity sFcγR (i) are generated by enzymatic cleavage of membrane-associated receptors or by an alternative splicing of the transmembrane region encoding exon and (ii) comprise only the extracellular domains or these domains plus the intracellular region of the membrane-associated molecules, respectively. Functional studies indicated that recombinant sFcγR bind mouse and human IgG subclasses with a binding profile identical to that of their membrane counterparts and inhibit FcγR-mediated functions such as immune complex binding or ADCC. In addition, it has been demonstrated that a mouse recombinant truncated sFcγRII inhibits antibody responses to T-dependent antigens as well as B-cell proliferation and that a human recombinant truncated sFcγRIIIB blocks the Ig production by activated human peripheral blood mononuclear cells. Finally, different immunoassays devised to detect and quantitate circulating sFcγR showed that sFcγR serum levels vary in circumstances such as injections of protein antigens, in parasitic infections, in tumor-bearing mice, in patients with multiple myeloma (MM), or upon infusions of IgG or Fcγ fragments in MM or immune thrombocytopenic purpura patients. The use of recombinant sFcγR, as well as the availability of monoclonal and polyclonal antibodies directed against different regions of these molecules, makes it possible to characterize further the biological effects of sFcγR and their biochemical and immunochemical characteristics, as well as to define their putative ligands on cell membranes.     

Karyotypic, palynological, and RAPD study on 12 taxa from two subsections of section Idaeobatus in Rubus L. and taxonomic treatment of R. ellipticus, R. pinfaensis, and R. ellipticus var. obcordatus

Twelve taxa belonging to two subsections of section Idaeobatus in Rubus L. from southwestern China were characterized by karyotypic, palynological, and random amplified polymorphic DNA (RAPD) data as follows: (1) The 12 taxa were all diploid species (2n = 2x = 14), among which the chromosome counts for R. mesogaeus var. oxycomus, R. subtibetanus, R. ellipticus var. obcordatus, R. inopertus var. echinocalyx, and R. stans were reported for the first time; (2) All taxa except for R. ellipticus and R. pinfaensis could be distinguished from each other by karyotype, pollen morphology, and RAPD markers. Karyotypes were mainly characterized by the difference in numbers and positions of submetacentric chromosomes and chromosomes with satellited pair, the index of the karyotypic asymmetry, and the ratio of the longest to the shortest chromosome. Pollen morphology were mainly characterized by the discrepancy in specific pollen size, P/E ratio, colpi width, distance between the apices of two ectocolpi, and exine ornamentation characters. The cluster results based on RAPD markers were consistent with morphology classification except for R. pinfaensis; (3) Based on the general data of karyotypic, palynological, and RAPD, R. ellipticus var. obcordatus should be treated as a species R. obcordatus, R. ellipticus and R. pinfaensis should be combined as R. ellipticus, and it was more reasonable to place the combinants and R. obcordatus into subsection Stimulantes rather than into subsection Pungentes.     

Association between polymorphisms in interleukin-4Rα and interleukin-13 and glioma risk: A meta-analysis

Introduction: It has been suggested that allergies are inversely associated with glioma risk. Single nucleotide polymorphisms in two allergy-related genes [interleukin (IL)-4Rα, IL-13] have been implicated in susceptibility to glioma; however, results from the published studies remained inconclusive. Methods: To derive a more precise relationship, we conducted a meta-analysis including seven case–control studies that investigated the influence of IL-4Rα rs1801275 and IL13 rs20541 polymorphisms on glioma risk. Data were extracted from these studies and pooled odds ratios (OR) with 95% confidence intervals (CI) were used to investigate the strength of the association. Results: Overall, the pooled analysis showed that there was no significant association between the IL-4Rα rs1801275 polymorphism and glioma risk (OR = 0.99, 95%CI: 0.79–1.25, AG/GG vs. AA). However, we found that the IL13 rs20541 variant genotypes (GA/AA) were significantly associated with reduced risk for glioma (OR = 0.85, 95%CI: 0.75–0.97, GA/AA vs. GG). In the stratified analyses by ethnicity, marginally significant association between the IL13 rs20541 polymorphism and decreased glioma risk was found among Asian populations in dominant models (OR = 0.84, 95%CI: 0.70–1.00, GA/AA vs. GG). Conclusions: This meta-analysis suggests that the IL13 rs20541 but not the IL-4Rα rs1801275 polymorphism may be a genetic predictor for glioma. More studies with larger sample size are warranted to further elucidate the impact of the IL13 rs20541 polymorphism on glioma risk.     

Genetic Association Study betweenSTK39 and CCDC62/HIP1R and Parkinson’s Disease

Background

The first large-scale meta-analysis of published genome-wide association studies (GWAS) in Parkinson’s disease (PD) identified 5 new genetic loci (ACMSD, STK39, MCCC1/LAMP3, SYT11, and CCDC62/HIP1R). Very recently, a large-scale replication and heterogeneity study also reported that STK39 and CCDC62/HIP1R increased risk of PD in Asian and Caucasian populations. However, their roles still remain unclear in a Han Chinese population from mainland China.

Methods

We examined genetic associations of STK39 rs2102808 and CCDC62/HIP1R rs12817488 with PD susceptibility in a Han Chinese population of 783 PD patients and 725 controls. We also performed further stratified analyses by the age of onset and accomplished in-depth clinical characteristics analyses between the different genotypes for each locus.

Results

No significant differences were observed in the minor allele frequency (MAF) among cases and controls at the two loci (STK39 rs2102808: OR = 1.06, 95% CI = 0.91, 1.23, P = 0.467; CCDC62/HIP1R rs12817488: OR = 0.88, 95% CI = 0.76, 1.01, P = 0.072). Subgroup analyses by the age of onset also showed no significant differences among different subgroups of the two loci. In addition, minor allele carriers cannot be distinguished from non-carriers based on their clinical features at the two loci.

Conclusions

We are unable to demonstrate the association between STK39 and CCDC62/HIP1R and PD susceptibility in a Han Chinese population from mainland China. Additional replication studies in other populations and functional studies are warranted to better validate the role of the two new loci in PD risk.     

Synthesis and cytokinin activity of (R)-(+)- and (S)-(−)-dihydrozeatins and their ribosides

(R)-(+)- and (S)-(?)-dihydrozeatins [(R)-(+)- and (S)-(?)-6-(4-hydroxy-3-methylbutylamino)purines, 1a and 1b] and their ribosides {(?)-6-[(R)-4-hydroxy-3-methylbutylamino]- and (?)-6-[(S)-4-hydroxy-3-methyl-butylamino]-9-β-D-ribofuranosylpurines, 3a and 3b} were synthesized and tested for their cytokinin activity by four bioassay systems, the growth of tobacco callus, the seed germination of lettuce, the fr. wt increase of excised radish cotyledons and the retardation of chlorophyll degradation in radish cotyledons. In tobacco callus bioassay, 1a was more active than 1b. The ribosides 3a and 3b were not less active than their corresponding aglycones 1a and 1b. In other bioassays used the activity followed the order: 1a >3a >1b >3b. In tobacco callus bioassay and lettuce seed germination, trans-zeatin [6-(4-hydroxy-3-methylbut-trans-2-enylamino)purine] showed stronger cytokinin activity than 1a.     

Molecular dynamics and molecular docking studies on E166A point mutant,R274N/R276N double mutant,and E166A/R274N/R276N triple mutant forms of class A β-lactamases

Bacterial resistance to β-lactams antibiotics is a serious threat to human health. The most common cause of resistance to the β-lactams is the production of β-lactamase that inactivates β-lactams. Specifically, class A extended-spectrum β-lactamase produced by antibiotic resistant bacteria is capable of hydrolyzing extended-spectrum Cephalosporins and Monobactams. Mutations in class A β-lactamases play a crucial role in substrate and inhibitor specificity. In this present study, the E166A point mutant, R274N/R276N double mutant, and E166A/R274N/R276N triple mutant class A β-lactamases are analyzed. Molecular dynamics (MD) simulations are done to understand the consequences of mutations in class A β-lactamases. Root mean square deviation, root mean square fluctuation, radius of gyration, solvent accessibility surface area, hydrogen bond, and essential dynamics analysis results indicate notable loss in stability for mutant class A β-lactamases. MD simulations of native and mutant structures clearly confirm that the substitution of alanine at the position of 166, Asparagine at 274 and 276 causes more flexibility in 3D space. Molecular docking results indicate the mutation in class A β-lactamases which decrease the binding affinity of Cefpirome and Ceftobiprole which are third and fifth generation Cephalosporins, respectively. MD simulation of Ceftobiprole-native and mutant type Class A β-lactamases complexes reveal that E166A/R274N/R276N mutations alter the structure and notable loss in the stability for Ceftobirole-mutant type Class A β-lactamases complexes. Ceftobiprole is currently prescribed for patients with serious bacterial infections; this phenomenon is the probable cause for the effectiveness of Ceftobiprole in controlling bacterial infections.     

Soluble cytokine receptors (sIL-2Rα, sIL-2Rβ) induce subunit-specific behavioral responses and accumulate in the cerebral cortex and basal forebrain

Soluble cytokine receptors are normal constituents of body fluids that regulate peripheral cytokine and lymphoid activity. Levels of soluble IL-2 receptors (sIL-2R) are elevated in psychiatric disorders linked with autoimmune processes, including ones in which repetitive stereotypic behaviors and motor disturbances are present. However, there is no evidence that sIL-2Rs (or any peripheral soluble receptor) induce such behavioral changes, or that they localize in relevant brain regions. Here, we determined in male Balb/c mice the effects of single peripheral injections of sIL-2Rα or sIL-2Rβ (0-2 μg/male Balb/c mouse; s.c.) on novelty-induced ambulatory activity and stereotypic motor behaviors. We discovered that sIL-2Rα increased the incidence of in-place stereotypic motor behaviors, including head up head bobbing, rearing/sniffing, turning, and grooming behavior. A wider spectrum of behavioral changes was evident in sIL-2Rβ-treated mice, including increases in vertical and horizontal ambulatory activity and stereotypic motor movements. To our knowledge, this is the first demonstration that soluble receptors induce such behavioral disturbances. In contrast, soluble IL-1 Type-1 receptors (0-4 μg, s.c.) didn't appreciably affect these behaviors. We further demonstrated that sIL-2Rα and sIL-2Rβ induced marked increases in c-Fos in caudate-putamen, nucleus accumbens and prefrontal cortex. Anatomical specificity was supported by the presence of increased activity in lateral caudate in sIL-2Rα treated mice, while sIL-2Rβ treated mice induced greater c-Fos activity in prepyriform cortex. Moreover, injected sIL-2Rs were widely distributed in regions that showed increased c-Fos expression. Thus, sIL-2Rα and sIL-2Rβ induce marked subunit- and soluble cytokine receptor-specific behavioral disturbances, which included increases in the expression of ambulatory activity and stereotypic motor behaviors, while inducing increased neuronal activity localized to cortex and striatum. These findings suggest that sIL-2Rs act as novel immune-to- brain messengers and raise the possibility that they contribute to the disease process in psychiatric disorders in which marked increases in these receptors have been reported.     

Commentary: The Rôle of Toxicology in Prevention and Precaution

Advocates of the Precautionary Principle have recently called for a “new science” to support the goals of precaution-based environmental and occupational health policy. While much attention has been given to epidemiology, the evidentiary science most relevant to precaution, or prevention, is toxicology. Opportunities for enhancing the rôle of toxicology in public policy must consider current biases in the field. Thus, rather than a “new science,” advocates for change should focus upon ensuring that current scientific methods are appropriate and that interpretations of scientific data are accurate.     

Direct connections between the R7/8 and R1–6 photoreceptor subsystems in the dipteran visual system

Summary Musca and related flies have three main photoreceptor subsystems. The R1–6 group has short axons that terminate in the cartridges of the first optic neuropile, the lamina. The cartridges are bypassed by the longer axons of R7 and R8, which run together to terminate at different levels in the underlying medulla neuropile. The present account describes a shallow, previously unidentified zone in the lamina within which R7/8 make glancing contact with R1–6. At the distal border of the cartridge over no more than 3–4 m depth, the tangentially directed short axon of R6 squeezes between the pair from R7 and R8, forming quite large areas of mutual contact (approximately 7 m²). Less frequently, R1 is contacted. At least some of these sites contain smaller membrane specialisations indistinguishable from the more numerous gap junctions found more proximally that interconnect the terminals of R1–6. The R7/8 junctions with R6 are of comparable size (0.15 m²) and likewise possess symmetrical membrane densities. They provide proposed pathways for direct electrical interaction to account for observed electrical input from R7/8 to the R1–6 subsystem. In two cases R7/8 was possibly postsynaptic to R1–6 at a multiple-contact synapse, but even if functional, these sites were so rare that they are unlikely to have much operational significance.     

Interaction of IFNλR1 with TRAF6 regulates NF-κB activation and IFNλR1 stability

IFNλR1 is a member of the class II cytokine receptor family, and it associates with IL‐10R2 to form a functional receptor complex, IFNλR. This receptor complex transduces signals from IFNλs (IFNλ1, IFNλ2, and IFNλ3), promoting antiviral and antiproliferative activities similar to those of type I IFNs. In an effort to further understand signal transduction through IFNλR1, we used bioinformatics analysis and identified a tumor necrosis factor receptor‐associated factor 6 (TRAF6)‐binding motif in the intracellular domain of IFNλR1. In subsequent immunoprecipitation and GST pull‐down assays, IFNλR1 was shown to immunoprecipitate with TRAF6 and was pulled down by GST‐TRAF6. Endogenous IFNλR1 and TRAF‐6 interaction implies that these proteins really interact in the cells. This interaction was abrogated upon mutation of the TRAF6‐binding motif in IFNλR1. Furthermore, the interaction between IFNλR1 and TRAF6 inhibited TRAF6‐induced NF‐κB activation, likely due to a reduction in TRAF6 autoubiquitination. Moreover, co‐expression of IFNλR1 with TRAF6 significantly increased the stability of IFNλR1, thereby prolonging its half‐life and enhancing its steady‐state level in cultured cells. J. Cell. Biochem. 113: 3371–3379, 2012. © 2012 Wiley Periodicals, Inc.     

Associations of the IL2Rα, IL4Rα, IL10Rα, and IFN γ R1 cytokine receptor genes with AIDS progression in a French AIDS cohort

We have performed an extensive analysis of Th1/Th2 cytokine receptors IL2Rα, IL4Rα, IL10Rα, and IFNγR1 gene polymorphisms to evaluate their impact on AIDS progression. The coding regions and promoters of these genes were sequenced in the genetics of resistance to immunodeficiency virus cohort, composed of 327 HIV-1-positive patients with extreme progression phenotypes, slow and rapid progressors, and of 446 healthy control subjects, all of them of Caucasian descent. Overall, 104 single nucleotide polymorphisms and four insertions/deletions with a minor allelic frequency higher than 1% were identified, 21 of them being newly characterized. We observed weak associations for 13 polymorphisms of IL2Rα, IL4Rα, IL10Rα, and IFNγR1, and 11 haplotypes of IL2Rα, IL4Rα, and IFNγR1. However, we could not relate these positive signals to any relevant biological information on the gene function. To affirm these putative associations in AIDS, further confirmation on other AIDS cohorts will be needed. This complete catalog of polymorphisms in IL2Rα, IL4Rα, IL10Rα, and IFNγR1 cytokine receptor genes should also be useful for investigating associations in other immune-related diseases.Electronic Supplementary Material Supplementary material is available for this article at